Spellpower

Spellpower is intrinsic to spells and the wand. By default, a spell has 100 base spellpower while the wand has 10, though these values are never shown to the player in-game (aside from base projectile damage). The robe does not have any spellpower and any effects of any material slotted onto the robe are completely unaffected by spellpower.

Materials with effects affected by spellpower will have their strength increased/decreased by a certain amount, depending on the spellpower change and how much spellpower affects the effect. For example, Poison Damage caused by the Noxious Spore material is 50% affected by spellpower. If it was slotted onto a wand, spellpower is decreased by 90% but since the material is only 50% affected by spellpower, this results in only 90% × 50% = 45% less Poison Damage.

If a Grade A Philospher Stone is slotted onto the same wand, its spellpower will increase from 10 to 35. However, spellpower is still 65% less than that of a spell, resulting in 65% × 50% = 32.5% less Poison Damage.

If, instead, all of the above was done to a spell instead of a wand, its spellpower will increase from 100 to 350 (+250% increase). However, since the material is only 50% affected by spellpower, this results in only 250% × 50% = 125% more Poison Damage.

Spellpower-Boosting Materials

 * Philospher Stone: up to +250% per slot
 * Chaos Butterfly: up to +200% per second
 * Soul Contract: up to +150% per slot
 * Extract of Monday: up to +100% per slot
 * Tonna Bricks: up to +100% per slot
 * Repulsor Energy: up to +50% per slot
 * Rainbow Prism: up to +25% per slot

Spellpower-Reducing Materials

 * Trick Bullet: -20% per hit
 * Lightning Rod: -25% on arc shot
 * Seashell: down to -25% per slot
 * Illusion Dust: down to -42.5% on first slot, -22.5% on each successive slot

Spellpower-Effected Materials

 * Green Belt: 100% affected
 * Guillotine Blade: 100% affected
 * Necrom-nomicon: 100% affected
 * Rune: 100% affected
 * Shade Spirit: 100% affected
 * Miniature Sun: 90% affected
 * Fire Crystal: approximately 83% affected
 * Rainbow Prism: approximately 83% affected
 * Sundial: approximately 83% affected
 * Rift Crystal: 80% affected
 * One-Sided Coin: approximately 68% affected
 * Caustic Ichor: 50% affected
 * Noxious Spore: 50% affected
 * Repulsor Energy: 50% affected
 * Vacuum Cleaner: 50% affected
 * Evercold Ice: approximately 47% affected
 * Harpy Feather: approximately 33% affected